Duck
VulcanSpirit
Richard & Alison Brunstrom
Mon 3 Feb 2014 12:45
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Here is a nice brown duck:
 As you can see, a fairly drab plain brown duck,
with a white eye ring, a bit of green on the wing bar and a touch of red to the
chest:
 But this isn't just any old duck, it's a New
Zealand Brown Teal Anas chlorotis, one of the rarest ducks in the world
- though this one, happily paddling round our boat with several friends
scrounging bread like any common or garden mallard, clearly doesn't realise just
how rare it is. There are about 1000 of them left; Great Barrier Island is now
their main stronghold but despite total protection since 1921 their numbers are
not rising, almost certainly because of predation from introduced cats and
rats.
Brown Teal, though not as showy as many ducks, are
very interesting - they seem to have arrived in NZ fairly recently but have
separated into three different species very rapidly. One of them, the
Auckland Island Teal Anas acklandica (Auckland Island is a very
remote NZ sub-antarctic island) is almost indistinuishable from other Brown Teal
but is now flightless, a striking illustration of how quickly a bird can
lose the ability to fly if there is no need for it. This is because flight uses
a huge amount of energy; if there is no need to fly then there is no point in
doing so and the resources required are put to better use. Which is OK, until
rats arrive.
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